求電子置換

WordNet

the act of putting one thing or person in the place of another: "he sent Smith in for Jones but the substitution came too late to help" (同)exchange, commutation
an event in which one thing is substituted for another; "the replacement of lost blood by a transfusion of donor blood" (同)permutation, transposition, replacement, switch

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(…の)『代用』,代理,置き換え《+for+名》

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/11/23 12:50:51」(JST)

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Electrophilic substitution reactions are chemical reactions in which an electrophile displaces a functional group in a compound, which is typically, but not always, a hydrogen atom. Electrophilic aromatic substitution reactions are characteristic of aromatic compounds, and are important ways of introducing functional groups onto benzene rings. The other main type of electrophilic substitution reaction is an electrophilic aliphatic substitution reaction.

Electrophilic aromatic substitution

In electrophilic substitution in aromatic compounds, an atom appended to the aromatic ring, usually hydrogen, is replaced by an electrophile. The most important reactions of this type that take place are aromatic nitration, aromatic halogenation, aromatic sulfonation and acylation and alkylating Friedel-Crafts reactions.

Electrophilic aliphatic substitution

In electrophilic substitution in aliphatic compounds, an electrophile displaces a functional group. This reaction is similar to nucleophilic aliphatic substitution where the reactant is a nucleophile rather than an electrophile. The four possible electrophilic aliphatic substitution reaction mechanisms are, S_E1, S_E2(front), S_E2(back) and S_Ei (Substitution Electrophilic), are also similar to the nucleophile counterparts S_N1 and S_N2. In the S_E1 course of action the substrate first ionizes into a carbanion and a positively charged organic residue. The carbanion then quickly recombines with the electrophile. The S_E2 reaction mechanism has a single transition state in which the old bond and the newly formed bond are both present.

Electrophilic aliphatic substitution reactions are:

Nitrosation
Ketone halogenation
Keto-enol tautomerism
aliphatic diazonium coupling
carbene insertion into C-H bonds
Carbonyl Alpha-Substitution Reactions

References

March, Jerry (1985). Advanced Organic Chemistry (5th ed.). Wiley.

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English Journal

Intramolecular Electrophilic Aromatic Substitution in Gas-phase Fragmentation of Protonated N-Benzylbenzaldimines.

Shen S1, Chai Y, Weng G, Pan Y.
Journal of the American Society for Mass Spectrometry.J Am Soc Mass Spectrom.2014 Sep;25(9):1662-9. doi: 10.1007/s13361-014-0935-7. Epub 2014 Jun 24.
In this study, the gas-phase fragmentations of protonated N-benzylbenzaldimines were investigated by electrospray ionization tandem mass spectrometry (ESI-MS(n)). Upon collisional activation, several characteristic fragment ions are produced and their fragmentation mechanisms are rationalized by ele
PMID 24957300

Anionic Chiral Tridentate N-Donor Pincer Ligands in Asymmetric Catalysis.

Deng QH1, Melen RL, Gade LH.
Accounts of chemical research.Acc Chem Res.2014 Aug 28. [Epub ahead of print]
Conspectus Tridentate monoanionic ligands known as "pincers" have gained a prominent place as ligands for transition metals and, more recently, for main-group metals and lanthanides. They have been widely employed as ancillary ligands for metal complexes studied inter alia in bond activation steps r
PMID 25166279

Trans-Selective Radical Silylzincation of Ynamides.

Romain E1, Fopp C, Chemla F, Ferreira F, Jackowski O, Oestreich M, Perez-Luna A.
Angewandte Chemie (International ed. in English).Angew Chem Int Ed Engl.2014 Aug 27. doi: 10.1002/anie.201407002. [Epub ahead of print]
The silylzincation of terminal ynamides is achieved through a radical-chain process involving (Me3 Si)3 SiH and R2 Zn. A potentially competing polar mechanism is excluded on the basis of diagnostic control experiments. The unique feature of this addition across the CC bond is its trans selectivit
PMID 25160825

Japanese Journal

Synthesis and Properties of 6-Methoxy- and 6-Dimethylamino-1-methylthio- and 1,3-Bis(methylthio)azulenes and Triflic Anhydride-Mediated Synthesis of Their Biaryl Derivatives

Shoji Taku,Maruyama Akifumi,Maruyama Mitsuhisa,Ito Shunji,Okujima Tetsuo,Higashi Junya,Toyota Kozo,Morita Noboru
Bulletin of the Chemical Society of Japan 87(1), 141-154, 2014
… 6-Methoxy- and 6-dimethylaminoazulenes with methylthio groups at the 1- or 1,3-positions have been prepared by electrophilic substitution of the corresponding azulenes with DMSO in the presence of acid anhydride, followed by treatment with Et3N. …
NAID 130004153257

Diastereoselective Synthesis of 3-Fluoro-2-substituted Piperidines and Pyrrolidines

Gichuhi Paul N.,Kuriyama Masami,Onomura Osamu
HETEROCYCLES 88(1), 331-346, 2014
… A facile procedure for synthesis of trans-3-fluoro-2-substituted piperidines by utilizing electrophilic fluorination of cyclic enamines and Lewis acid mediated nucleophilic substitution has been developed. …
NAID 120005365971